Treatment (2011)

All his life, Leonard has dreamed of being a famous filmmaker, but he's better at making excuses than making art. A chance encounter with a wasted A-list movie star could be his lucky break. All he has to do is come up with $15,000 to join the actor at a luxury rehab facility, where their friendship can blossom into wealth and glory. Leonard checks into treatment under false pretences, but soon discovers that addiction comes in many forms.

Unfortunately the movie Treatment is not yet available on HBO Max.